• Constants - Integer and Float.
• Keywords - while, if, for, int, float, char, main, printf, scanf, break, do, typedef, static.
• Identifiers - It can have alpha (lowercase) numeric combination, start with alphabet or underscore and only first 20 characters to be picked and remaining to be dropped.
• Logical operators - &&, ||, !.
• Arithmetic operators - +, −, /, ∗.
• Relational operators - >, >=, <, <=, ! =.
• Unary Operators - −−, ++, ∗.